1. Field of the Invention
The present invention relates to a chip coil, which is used for, for example, compact communication equipment or electronic devices.
2. Description of the Related Art
As sizes and weights of electronic devices are reduced, requests for reduction in size (integration onto a chip) of electronic components increase. As disclosed in Japanese Patent Application Laid-Open No. 9-219318, for example, a chip inductor, which is a chip electronic component, forms a coil made by winding a conductive wire around a square pole winding drum, which has flange-shaped brims protruding from both edges. And, formed on part of the end faces of those brims are plated electrodes.
FIG. 8 shows an example of a configuration of a conventional chip inductor. A chip inductor 60 shown in FIG. 8 has electrodes 65 and 67, which are formed on the entire surface of the brims 62 and 64 of a core, and is mounted upon a printed circuit board so that the direction of the length thereof can be the same as the running direction of patterns 61 and 63, which are signal lines on that printed circuit board.
The results from carrying out an electromagnetic field simulation for the above-described conventional chip inductor show that, as shown in FIG. 9, concentration of magnetic fluxes has occurred at the portions indicated by symbols (O) in the brims 62 and 64, which are components of the core. In other words, as is seen from FIGS. 8 and 9, the conventional chip inductor has a configuration where electrodes 65 and 67 are formed at the magnetic flux concentrated portions of the core.
There are problems with the conventional inductor in which the above-described configuration causes increase in magnetic loss and decrease in the Q value.
The present invention has been developed in view of the above-described problems, and aims to provide a chip coil, which reduces magnetic loss and prevents decrease in sensitivity characteristics and the Q value and is suitable for use as an antenna for wireless communications by mounting on various wireless communication equipment (e.g., radio frequency identification (RFID)).